It is also unclear whether or not galactic-scale
inflows produced by the interaction with satellite
galaxies can directly fuel the central super-massive
black holes (SMBHs) to produce AGNs. One
possibility is that the galactic-scale
inflow can enhance the star formation in a galaxy
center to build up a pseudo-bulge/bar component,
as indicated by Figure REF , which
in turn can halp drive cold gas toward the SMBH.
Consistent with this, a large fraction of the host galaxies
of AGNs are observed to contain pseudo-bulge structures [1]}.
Alternatively, the interactions with satellites
may distort galaxy disks, and the gravitational
torque of the non-axisymmetric disks can help to transport cold gas into the galactic center to feed
the SMBH [2]}. These secular structures may persist long after the original interaction,
providing a long lasting engine to support AGN
activities. Clearly, further investigations
are needed to verify such a scenario.
